Artificial tooth.



W. N. KIDDER.

ARTIFICIAL TOOTH.

APPIJIOATION FILED arm. a, 1913.

1,108,449. Patented Aug. 25, 1914.

zr/vfssss z/w avrw? m w/vm/r/wm WILLIAM N. KIDDER, OF PROVIDENCE, RHODE ISLAND.

ARTIFICIAL Toorn.

Specification of Letters Patent.

Patented Aug. 25, 1914.

Application filed September 2, 1913. Serial No. 787,563.

To all whom it may concern:

Be it known that I, WILLIAM N. Kinnnn, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Artificial Teeth, of which the following is a specification.

My invention relates to artificial teeth, and more especially to the construction of metal backing plates therefor arranged to be secured to porcelain crowns or fronts.

In the accompanying sheet of drawings, Figure 1 represents a front elevation of my improved tooth; Fig. 2 is a back elevation of the same (the metalbacking or anchor plate removed); Fig. 3 is a side elevation, correspending with Fig. 2; Fig. 4 is an enlarged perspective view of themetal key, disconnected from the back of the porcelain facing; Fig. 5 is a vertical section, enlarged, taken through the center of my improved tooth, showing the porcelain facing portionrigidly secured to' the metal backing plate, and alsosho'wing the manner of connecting the parts; Fig. 6 is a perspective view, showing the backing plate detached from the front porcelain member; Fig. 7 is an en larged cr0sssection, taken on line 77 of Fig. 1; Fig. 8 shows a reanelevation of the untrimmed backing plate, formed from comparatively thin metal stock; the recessed cavity itself being the exact counterpart, of

and adapted to snugly receive the metal key fixed to the back of the porcelain facing; Fig. 9 is a cross-section of the plate, taken on line 9-9 0f Fig. 8; and Fig. 10 is a side elevation, showing a manner of securing my improved tooth/crown to a natural toothroot retaii'iedin, the jaw.

In the drawing?! a; designates a porcelain facing or artificial-crown having a plurality of metal pins 19, as platinum, embedded and baked therein and extending at substantially right angles from the rear plane face a and forming a Well-known article of manufacture, said crown usually having an endwise extension (1 which is or may be ground off when the facing member is employed in conmotion .with certain dental operations. Crowns of such construction are stronger and very much less liable to become accidentally broken than porcelain facing members inwhich the lugs or recesses are formed integral therewith.

In my improved artificial tooth construction I employ an apertured metal block b, which may be termed a key or gib, the same having oppositely facing plane and inclined sides J 71 and opposed dovetail lateral edges 6 in practice these blocks are alike and interchangeable, Fig. 4. The pins 7) of the porcelain facings are inserted in the apertures p of the blocks and permanently secured thereto by rivet ng or soldering. As thus constructed, each of the block-carrying facings or crowns is a duplicate of the others exact counterpart of the said key I): that is,

the inclined sides (2 (i d conform accurately to the respective sides 11 7r. b of the key. Thus, it is obvious that a porcelain tooth or crown (I, having a plane rear face (1,

to which is fixed the metal key element 6 may be taken indiscriminately from a mass of similarly provided teeth and be readily interlocked with one of the said metal backing plates 0 by simply inserting the key into the cavity cl until the faces a and 0 engage each other, say at the point m, as in 'dicated in dotted lines, Fig. at the same time pressing the plate in the arrow direction 1, thereby causing the latter to swing outward, see arrow 2. the action of the undercut or dovetailed edges 7;, (Z meanwhile guiding the lower or thinner end of the wedge part inward (see arrow 3) until the parts I) and d snugly engage each other. At the same time, too, the lower or incisive edge a of the porcelain crown is protected by the edge of the plate 0, as indicated in said Fig. 5.

In my improved metal plate or back the recess (Z formed therein is closed on all sides, thereby completely covering, protect ing and concealing the gib-block, thus preventing the entrance of injurious foreign matter, the action ofwhich latter would tend to shorten the life of the tooth.

By means of my impr wement the incisive edge of the plate may be inturned or adapted to receive the adjacent end of the root; thelatter is provided with an enlarged longitudinally extending cavity, into which cavity a metal post h secured to thefiange h, is fixedly inserted. It may be added that the several contiguous faces where the parts are joined are or may be suitably cemented together in a well-known manner. I prefer to also cement the key 1) into the wedgeshaped interlocking recess d of the backing plate 0. In order to render the inner surface of the plate smooth and symmetrical, or

semi-oval cross-sectionally, substantially as represented in Fig. 7, the same may be effected or built up by flowing gold solder over the surface to the desired extent.

I claim:

L A metal backing member for artificial teeth, the same comprising a plate having a dovetail recess therein forming a seat arranged to receive and support a metal gib or block element fixed to an artificial tooth, said recess being closed on all sides and adapted to cover and completely conceal said element when the latter is seated in the recess.

2. In an artificial tooth, the combination of a porcelain facing or crown member, a metal gib-block rigidly secured to the back race of the crown, said gib having a dovetail form and being materially thicker at the root end than at the incisive portion of the crown, and a metal backing plate having a recess therein the counter-part of said gib, in which recess said gib is firmly seated, said recess being closed on all sides and completely concealing and-protecting the gib.

In testimony whereof I have afiixed my signature in presence of twowitnesses.

lVILLIAM N. KIDDER. Witnesses:

GEO. H. REMI GTON, CALVIN H. BROWN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

